diff options
Diffstat (limited to 'compiler/rustc_feature/src/active.rs')
| -rw-r--r-- | compiler/rustc_feature/src/active.rs | 69 |
1 files changed, 41 insertions, 28 deletions
diff --git a/compiler/rustc_feature/src/active.rs b/compiler/rustc_feature/src/active.rs index a02c04ecd3e..83961647bd4 100644 --- a/compiler/rustc_feature/src/active.rs +++ b/compiler/rustc_feature/src/active.rs @@ -7,15 +7,6 @@ use rustc_span::edition::Edition; use rustc_span::symbol::{sym, Symbol}; use rustc_span::Span; -macro_rules! set { - ($field: ident) => {{ - fn f(features: &mut Features, _: Span) { - features.$field = true; - } - f as fn(&mut Features, Span) - }}; -} - #[derive(PartialEq)] enum FeatureStatus { Default, @@ -23,16 +14,19 @@ enum FeatureStatus { Internal, } -macro_rules! declare_features { - (__status_to_enum active) => { +macro_rules! status_to_enum { + (active) => { FeatureStatus::Default }; - (__status_to_enum incomplete) => { + (incomplete) => { FeatureStatus::Incomplete }; - (__status_to_enum internal) => { + (internal) => { FeatureStatus::Internal }; +} + +macro_rules! declare_features { ($( $(#[doc = $doc:tt])* ($status:ident, $feature:ident, $ver:expr, $issue:expr, $edition:expr), )+) => { @@ -43,7 +37,10 @@ macro_rules! declare_features { &[$( // (sym::$feature, $ver, $issue, $edition, set!($feature)) Feature { - state: State::Active { set: set!($feature) }, + state: State::Active { + // Sets this feature's corresponding bool within `features`. + set: |features| features.$feature = true, + }, name: sym::$feature, since: $ver, issue: to_nonzero($issue), @@ -58,8 +55,9 @@ macro_rules! declare_features { pub declared_lang_features: Vec<(Symbol, Span, Option<Symbol>)>, /// `#![feature]` attrs for non-language (library) features. pub declared_lib_features: Vec<(Symbol, Span)>, - /// Features enabled for this crate. - pub active_features: FxHashSet<Symbol>, + /// `declared_lang_features` + `declared_lib_features`. + pub declared_features: FxHashSet<Symbol>, + /// Individual features (unstable only). $( $(#[doc = $doc])* pub $feature: bool @@ -67,16 +65,33 @@ macro_rules! declare_features { } impl Features { + pub fn set_declared_lang_feature( + &mut self, + symbol: Symbol, + span: Span, + since: Option<Symbol> + ) { + self.declared_lang_features.push((symbol, span, since)); + self.declared_features.insert(symbol); + } + + pub fn set_declared_lib_feature(&mut self, symbol: Symbol, span: Span) { + self.declared_lib_features.push((symbol, span)); + self.declared_features.insert(symbol); + } + pub fn walk_feature_fields(&self, mut f: impl FnMut(&str, bool)) { $(f(stringify!($feature), self.$feature);)+ } - /// Is the given feature active? - pub fn active(&self, feature: Symbol) -> bool { - self.active_features.contains(&feature) + /// Is the given feature explicitly declared, i.e. named in a + /// `#![feature(...)]` within the code? + pub fn declared(&self, feature: Symbol) -> bool { + self.declared_features.contains(&feature) } - /// Is the given feature enabled? + /// Is the given feature enabled, i.e. declared or automatically + /// enabled due to the edition? /// /// Panics if the symbol doesn't correspond to a declared feature. pub fn enabled(&self, feature: Symbol) -> bool { @@ -93,11 +108,10 @@ macro_rules! declare_features { pub fn incomplete(&self, feature: Symbol) -> bool { match feature { $( - sym::$feature => declare_features!(__status_to_enum $status) == FeatureStatus::Incomplete, + sym::$feature => status_to_enum!($status) == FeatureStatus::Incomplete, )* // accepted and removed features aren't in this file but are never incomplete - _ if self.declared_lang_features.iter().any(|f| f.0 == feature) => false, - _ if self.declared_lib_features.iter().any(|f| f.0 == feature) => false, + _ if self.declared_features.contains(&feature) => false, _ => panic!("`{}` was not listed in `declare_features`", feature), } } @@ -108,12 +122,11 @@ macro_rules! declare_features { pub fn internal(&self, feature: Symbol) -> bool { match feature { $( - sym::$feature => declare_features!(__status_to_enum $status) == FeatureStatus::Internal, + sym::$feature => status_to_enum!($status) == FeatureStatus::Internal, )* // accepted and removed features aren't in this file but are never internal // (a removed feature might have been internal, but it doesn't matter anymore) - _ if self.declared_lang_features.iter().any(|f| f.0 == feature) => false, - _ if self.declared_lib_features.iter().any(|f| f.0 == feature) => false, + _ if self.declared_features.contains(&feature) => false, _ => panic!("`{}` was not listed in `declare_features`", feature), } } @@ -123,9 +136,9 @@ macro_rules! declare_features { impl Feature { /// Sets this feature in `Features`. Panics if called on a non-active feature. - pub fn set(&self, features: &mut Features, span: Span) { + pub fn set(&self, features: &mut Features) { match self.state { - State::Active { set } => set(features, span), + State::Active { set } => set(features), _ => panic!("called `set` on feature `{}` which is not `active`", self.name), } } |